U.S. patent number 6,620,184 [Application Number 09/795,808] was granted by the patent office on 2003-09-16 for release mechanism for grasping device.
This patent grant is currently assigned to Microline Inc.. Invention is credited to Henri F. de Guillebok, Hughes I. de Laforcade.
United States Patent |
6,620,184 |
de Laforcade , et
al. |
September 16, 2003 |
Release mechanism for grasping device
Abstract
A ratchet release mechanism for a medical device. The release
mechanism permits both a smooth and a stepped actuation of a
grasper on a distal end of the medial device. The medical device
has a fixed handle and a movable handle. The release mechanism
comprises an elongated toothed plate arrangement supported in a
release housing and an elongated smooth plate arranged adjacent the
toothed plate arrangement in the release housing. The release
housing is pivotably supported between the handles to permit the
handles to move in a stepped or a smooth manner to effect actuation
of the grasper.
Inventors: |
de Laforcade; Hughes I.
(Manchester, MA), de Guillebok; Henri F. (Manchester,
MA) |
Assignee: |
Microline Inc. (Beverly,
MA)
|
Family
ID: |
25166502 |
Appl.
No.: |
09/795,808 |
Filed: |
February 28, 2001 |
Current U.S.
Class: |
606/205;
606/207 |
Current CPC
Class: |
A61B
17/1285 (20130101) |
Current International
Class: |
A61B
17/128 (20060101); A61B 17/12 (20060101); A61B
017/28 () |
Field of
Search: |
;606/170,171,205,206,207,208
;81/304,306,318,319,320,324,369,329,331,338,339,340,341 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Milano; Michael J.
Assistant Examiner: Bui; Vy Q.
Attorney, Agent or Firm: Halgren; Don
Claims
We claim:
1. A ratchet release mechanism for a medical device permitting a
smooth and a stepped actuation of a grasper on a distal end of said
medial device, said medical device having a fixed handle and a
movable handle, said release mechanism comprising: an elongated
toothed plate arrangement supported in a release housing; an
elongated smooth plate arranged adjacent said toothed plate
arrangement in said release housing, said release housing being
pivotably supported between said handles to permit said handles to
move in a stepped or a smooth manner to effect actuation of said
grasper, wherein said release housing includes a slot with a
movable pin extending therethrough, wherein movement of said
movable pin effects arcuate displacement of said toothed plate
arrangement with respect to said smooth plate.
2. The ratchet release mechanism as recited in claim 1, wherein
said elongated plates are disposed about a common pivot pin.
3. The ratchet release mechanism as recited in claim 1, wherein
said smooth plate arrangement has a slot therein and said toothed
plate arrangement has a slot therein, said slots having a commonly
aligned forwardmost end.
4. The release mechanism as recited in claim 3, wherein said fixed
handle has a ratchet point thereon which is engageable with said
toothed plate arrangement.
5. The release mechanism as recited in claim 3, wherein said
toothed plate arrangement is fixedly supported in said release
housing.
6. The release mechanism as recited in claim 5, wherein said smooth
plate arrangement is pivotably supported in said release
housing.
7. The release mechanism as recited 2, wherein said release housing
is pivotably supported on said movable handle.
8. The release mechanism as recited in claim 7, including a leaf
spring attached to said fixed handle to bias said toothed plate
assembly in said release housing against said pivot pin.
9. The release mechanism as recited in claim 7, wherein said
release housing has a bridging portion which is pressable to
displace said toothed plate arrangement in said release housing out
of engagement with said ratchet point, and thus permit smooth
action of said grasper.
10. A ratchet release mechanism for a medical device permitting a
smooth and a stepped actuation of a grasper on a distal end of said
medial device, said medical device having a fixed handle and a
movable handle, said release mechanism comprising: an elongated
toothed plate arrangement supported in a release housing; an
elongated smooth plate arranged adjacent said toothed plate
arrangement in said release housing, said release housing being
pivotably supported between said handles to permit said handles to
move in a stepped or a smooth manner to effect actuation of said
grasper, said elongated plates are disposed about a common pivot
pin, said release housing includes a slot with a pin extending
therethrough, wherein movement of said pin effects arcuate
displacement of said toothed plate arrangement with respect to said
smooth plate, said smooth plate arrangement having a slot therein
and said toothed plate arrangement having a slot therein, said
slots having a commonly aligned forwardmost end; wherein said fixed
handle has a ratchet point thereon which is engageable with said
toothed plate arrangement; and wherein said toothed plate
arrangement is fixedly supported in said release housing, said
smooth plate arrangement being pivotably supported in said release
housing, and wherein said release housing is pivotably supported on
said movable handle.
11. A method of stepwise grasping and manipulating a body tissue in
a laparoscopic procedure, by an elongated grasping device, said
method comprising the steps of: pivoting a plurality of elongated,
adjacently disposed arcuate members about a common pivot axis
through their rear end thereof, each arcuate member supported in a
housing, wherein at least one of said arcuate members has an upper
edge with a plurality of teeth thereon, and each of said arcuate
members having a slot in a forward end thereof; engaging at least
one of said arcuate members by a ratchet point in said grasping
device to move a grasper jaw arrangement on a distal end of said
grasper device to secure a tissue therein; and moving one of said
arcuate members with respect to the remainder of said arcuate
members to effect release of said at least one of said arcuate
members and unlocking of said grasper jaw arrangement and release
of tissue therefrom.
12. The method as recited in claim 11, including the step of:
moving a pin transversely through said slots in said forward end of
said plurality of arcuate members to effect said moving of said at
least one of said arcuate members with respect to the remainder of
said arcuate members thus effecting pivoting movement
therebetween.
13. The m et hod as recited in claim 12, where in at least one of
said arcuate members has a smooth edge and the remainder of said
plurality of arcuate members have said teeth thereon.
14. The method as recited in claim 13, wherein said slot in said
arcuate member having a smooth upper edge thereon is arranged out
of alignment with respect to said slots in the remainder of said
arcuate members.
15. The method as recited in claim 14, wherein said slot in said
arcuate member having a smooth upper edge thereon has a rearmost
portion arranged at an angle with respect to a forward portion
thereof.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to handle assemblies for manipulable
surgical devices, and more particularly to release mechanisms
within that handle assembly.
2. Prior Art
Laparoscopic surgery may be defined as minimally invasive surgery
upon a patient, utilizing small or miniaturized medical devices by
which body tissue is cut, removed or cauterized by small
manipulable devices through small incisions or openings within the
patient's body.
One device needed for such surgery may be characterized as a
grasper or dissector. Such a device may be utilized to grab,
dissect, treat or move tissue out of the surgical situs where other
tissue may be surgically treated.
There exists a need for a device which will permit ready
manipulation of tissue of any particular size or thickness
encountered which can be grasped and maintained or manipulated
readily by a single hand of an operating surgeon, and which
protects the surgeon from high voltage electricity when cauterizing
a patient.
It is therefore an object of the present invention, to provide a
grasper or dissector handle arrangement which improves upon the
prior art.
It is a further object of the present invention, to provide a
handle mechanism of a grasper or dissector device which permits
maintaining or manipulating body tissue of any thickness
encountered, by use of a simple release mechanism in the handle of
the device.
It is yet a further object of the present invention, to provide a
release mechanism which permits that medical grasper device to be
multi-funtional, to maintain and/or to immediately release a
grasping or treatment configuration to that medical device and to
provide electrical high voltage insulation when cautery is applied
to the handpiece device.
It is still yet a further object of the present invention to
provide a handle release mechanism for a grasper device which is
very simple to operate and inexpensive to manufacture so as to
provide optimum economic conditions for the medical community.
BRIEF SUMMARY OF THE INVENTION
The present invention relates to a handle assembly release
mechanism for an elongated medical device such as a laparoscopic
grasper or dissector. The handle assembly comprises an elongated
frame element having a barrel housing at a first or uppermost end
thereof, a cautery pin and elongated ring portion at a second or
lowermost portion thereof for receipt of the operator's fingers.
The barrel housing is arranged to receive the proximal end of an
elongated outer shaft of the grasper or dissector device. The
elongated shaft of that grasper device has a distal end at which a
pair of forceps are pivotably disposed. The forceps device at the
distal end of the elongated shaft are opened and closed in a known
manner by reciprocal movement of an inner shaft. The inner shaft
has a proximal end that extends through the barrel housing and is
in pivotable attachment with a movable handle member. The movable
handle member pivots about a rear pivot pin in a rear pin opening
in the frame of the fixed handle assembly.
A ratchet point is arranged at a mid-location of the elongated
frame portion of the fixed handle assembly, and a biasing spring is
arranged in that fixed handle assembly thereadjacent.
The release mechanism is arranged between the movable handle and
the fixed handle. The release mechanism comprises a housing defined
by a pair of elongated parallel plates. The elongated parallel
plates have a bridging portion joining them therebetween. The
release mechanism is attached at its rearmost end by the rear pin,
to the rear pin hole in the movable handle. The release mechanism
is pivotable about that rear pin.
A plurality of elongated arcuately-shaped toothed plates are
disposed between the side members of the release mechanism. The
plurality of arcuately shaped plates is comprised of a main toothed
plate and several arcuately-shaped toothed sub-plates. The toothed
plates have a first or forward end and a second or rear end. The
main tooth plate has a rear pin hole at its rearward most end. The
rear pin which extends through a release mechanism housing extends
also through the rear pin hole of the main toothed plate. The
forward end of the main toothed plate has a forward pin hole
therethrough. A forward pin is disposed through the forward pin
hole of the main toothed plate and is received in a pair of holes
in the forward end of the release mechanism housing.
An elongated arcuately-shaped smooth plate is arranged adjacent the
plurality of toothed elongated plates within the release mechanism
housing. The elongated smooth plate has a first or forward end and
a second or a rear end. The rear end of the arcuately-shaped smooth
plate has a rear pin hole therethrough. The rear pin of the tooth
plates and the release mechanism housing also passes through the
rear end hole of the smooth plate.
The main toothed plate and the sub-plates with teeth, have an
elongated slot extending in a generally forwardly to rearwardly
direction.
The slot in the toothed plates has a first or forward end and a
second or rearward end.
The smooth elongated plate has an elongated slot at its forwardmost
end. The smooth plate is arranged to be pivotally juxtaposed
adjacent the array of toothed plates. The smooth plate has its slot
arranged at an angle with respect to the slot of the toothed
plates. The slot in the smooth plate has a first end which is in
alignment with the slot in the first or forward end of the toothed
plates.
A pair of released buttons are arranged on each side of the pair of
parallel plates defining the housing of the release mechanism. The
release buttons are connected by a button pin extending
therebetween. The button pin also extends through the slot in the
toothed plate assembly as well as in the slot of the smooth
plate.
In operation of the release mechanism of the present invention the
operating surgeon would have fingers arranged through the fixed
handle and the movable handle. Respective arcuate movement of the
pivotable or movable handle towards the fixed handle would cause
the inner shaft attached to the distalmost end of the movable
handle to be pulled rearwardly and thus effect the closing of the
forceps on the distalmost end of the grasper device. When the
release button is in its rearwardmost position, with its connecting
pin within the rearwardmost location of the slot within the release
mechanism housing and also in the rearwardmost position in the slot
of the toothed plate assembly and the slot in the smooth plate,
movement of the movable handle with respect to the fixed handle is
unhindered, thus permitting the surgeon to open and close the
forceps of the medical device, at will. This is permitted by virtue
of the smooth plate being pivoted upwardly about the rear pin, to a
location where the upper edge of the smooth plate is disposed above
the teeth in the toothed plate assembly. In that manner, the
ratchet point in the framed portion of the fixed handle assembly is
not permitted to engage the teeth within the toothed plate
assembly.
When the movable handle member is pulled rearwardly and the release
button arrangement is pushed forwardly in its slot within the
release mechanism housing, the release button connecting pin is
pushed forward in the slot of the toothed plate assembly as well as
in the slot for the smooth plate. The smooth plate is thus cammed
downwardly and pivoted about its rearwardmost pivot pin and pin
hole due to the camming action of the release button pin in the
slot therein. Thus the teeth in the main toothed plate and attached
toothed sub-plates are exposed to the ratchet point in the fixed
handle assembly, and those toothed plates are biased theretoward by
the leap spring within the fixed handle assembly.
The attending surgeon may thus squeeze the movable handle towards
the fixed handle thus ratcheting downwardly on the handle assembly.
This permits the forceps to be closed in a stepwise manner. A body
tissue may be grasped firmly within those forceps and held there by
the ratchet point engaging any of the series of teeth within the
elongated toothed plates.
Prompt release of the forceps from the tissue is effected by a
downward pressure on the trigger-like bridging portion of the
release mechanism housing. This downward pressure on the bridging
portion of the released mechanism housing pushes the leaf spring
downwardly and permits the movable handle to be displaced away from
the fixed handle thus permitting the opening the forceps and
permitting release of the body tissue from therebetween.
It is thus to be noted, that the unique release mechanism permits a
wide range of angular openings of the forceps, to permit a locking
thereat, thus enabling the operating physician to grasp almost any
size body tissue thereby. The simple release of this mechanism,
being effected by a trigger-like pull on the bridging portion of
the release mechanism housing thus overides the engagement of the
ratchet point with the teeth on the toothed plates, permitting a
fast and responsive release of the tissue and actuating the grasper
mechanism for a subsequent grasping operation.
The invention thus comprises a ratchet release mechanism for a
medical device permitting a smooth and a stepped actuation of a
grasper on a distal end of the medial device. The medical device
has a fixed handle and a movable handle. The release mechanism
comprises an elongated toothed plate arrangement supported in a
release housing. An elongated smooth plate is arranged adjacent the
toothed plate arrangement in the release housing. The release
housing is pivotably supported between the handles to permit the
handles to move in a stepped or a smooth manner to effect actuation
of the grasper. The elongated plates are disposed about a common
pivot pin. The release housing includes a slot with a pin extending
therethrough, wherein movement of the pin effects arcuate
displacement of the toothed plate arrangement with respect to the
smooth plate. The smooth plate arrangement has a slot therein and
the toothed plate arrangement has a slot therein, all of the slots
having a commonly aligned forwardmost end. The fixed handle has a
ratchet point thereon which is engageable with the toothed plate
arrangement. The toothed plate arrangement is fixedly supported in
the release housing. The smooth plate arrangement is pivotably
supported in the release housing. The release housing is pivotably
supported on the movable handle. A leaf spring is attached to the
fixed handle to bias the toothed plate assembly in the release
housing against the pivot point. The release housing has a bridging
portion which is pressable to displace the toothed plate
arrangement in the release housing out of engagement with the
ratchet point, and thus permit smooth action of the grasper.
The invention also comprises a method of stepwise grasping and
manipulating a body tissue in a laparoscopic procedure, by an
elongated grasping device, said method comprising the steps of:
pivoting a plurality of elongated, adjacently disposed arcuate
members about a common pivot axis through their rear end thereof,
each arcuate member supported in a housing, wherein at least one of
the arcuate members has an upper edge with a plurality of teeth
thereon, each of the arcuate members having a slot in a forward end
thereof; engaging at least one of the arcuate members by a ratchet
point in the grasping device to move a grasper jaw arrangement on a
distal end of the grasper device to secure a tissue therein; and
moving one of the arcuate members with respect to the remainder of
the arcuate members to effect release of the arcuate members and
unlocking of the grasper jaw arrangement and release of tissue
therefrom. The method includes moving a pin transversely through
the slots in the forward end of the plurality of arcuate members to
effect the moving of the one of the arcuate members with respect to
the remainder of the arcuate members thus effecting pivoting
movement therebetween. At least one of the arcuate members has a
smooth edge and the remainder of the plurality of arcuate members
have teeth on a upper edge thereof. The slot in the arcuate member
having a smooth upper edge thereon is arranged out of alignment
with respect to the slots in the remainder of the arcuate members.
The slot in the arcuate member having a smooth upper edge thereon
has a rearmost slot portion arranged at an angle with respect to a
forward slot portion thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and advantages of the present invention will be come
more apparent when viewed in conjunction with the following
drawings, in which:
FIG. 1 is a side elevation view of a grasper device constructed
according to the principles of the present invention;
FIG. 2 is a plan view of the release mechanism of the present
invention;
FIG. 3 is a view taken along the: lines 3--3 of FIG. 2;
FIG. 4 is a side elevational of the fixed handle assembly of the
present invention;
FIG. 5 is a side elevational view of a main toothed plate;
FIG. 6 is a edge view of the main toothed plate shown in FIG. 5
with an attachment of toothed sub-plates thereon;
FIG. 7 is a side elevational view of the view shown in FIG. 6;
and
FIG. 8 is a planned view of a smooth plate of the plate assembly
portion of the release mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawing in detail, and particularly to FIG. 1,
there is shown the present invention which comprises a handle
assembly 10 with a release mechanism 12, for an elongated medical
device such as a laparoscopic grasper 14 or the like. The handle
assembly 10, as may be seen in FIGS. 1 and 4, comprises an
elongated frame element 16 having a barrel housing 18 at a first or
uppermost end thereof with an insulated dissector-coupled
electrical contact 19 thereat. An elongated ring portion 20 is at a
second or lowermost portion of the frame 16 for receipt of the
surgeon's fingers. The barrel housing 18 is arranged to receive the
proximal end 22 of an elongated outer shaft 24 of the grasper
device 14. The elongated shaft 24 of that grasper device 14 has a
distal end 26 at which a pair of forceps (or dissectors) 28 are
pivotably disposed. The forceps device 28 at the distal end 26 of
the elongated shaft 24 are opened and closed in a known manner by
reciprocal movement of an inner shaft 30. The inner shaft 30 has a
proximal end that extends through the barrel housing 18 and is in
pivotable attachment with an upper end of an elongated movable
handle member 32, as may be seen in FIG. 1. The movable handle
member 32 pivots about an upper pivot pin 33 in an upper pin
opening 35 in the frame 16 of the fixed handle assembly 10, as
shown in FIGS. 1 and 4.
A ratchet point 40 is arranged at a mid-location of the elongated
frame portion 16 of the fixed handle assembly 10, and a generally
linear biasing spring 42 is securely arranged by a screw 43 in that
fixed handle assembly 10 thereadjacent, as is shown in FIG. 4.
The release mechanism 12 is pivotably arranged between the movable
handle 32 and the fixed handle 10, as shown in FIG. 1. The release
mechanism 12 comprises a housing 48 defined by a pair of elongated
parallel side members or plates 50 and 52, as may be seen in FIGS.
2 and 3. The elongated parallel plates 50 and 52 of the housing 48
have a bridging portion 54 joining them therebetween. The release
mechanism 12 is attached at its rearmost end by the rear pin 34, to
the rear pin hole 36 in the movable handle 32, as shown in FIG. 1.
The release mechanism 12 is pivotable about that rear pin 34, in
the direction as indicated by arrow "Z" in FIG. 1.
An elongated, arcuately-shaped toothed plate assembly 60 is
disposed between the side members 50 and 52 of the release
mechanism 12, as shown in FIGS. 2 and 3. The plate assembly 60 is
comprised of an elongated, arcuately-shaped main toothed plate 62,
as shown in FIG. 5, and several arcuately-shaped toothed sub-plates
64, as shown in FIGS. 6 and 7. The toothed plates 62 and 64 have a
first or forward end 66 and a second or rear end 68. The main
toothed plate 62 has a rear pin hole 70 at its rearward most end
68. The rear pin 34 which extends through the release mechanism
housing 48 extends also through the rear pin hole 70 of the main
toothed plate 62, as may be "visualized" in FIG. 2.
The forward end 66 of the main toothed plate 62 has a forward pin
hole 72 therethrough, as shown in FIGS. 5 and 7. A forward pin 74
is disposed through the forward pin hole 72 of the main toothed
plate 62 and is received in a pair of holes 76 and 78 in the
forward end of the release mechanism housing 48, as may be seen in
FIG. 2.
An elongated, arcuately-shaped smooth plate 80, as may be seen in
FIG. 8, is pivotably arranged adjacent the plurality of toothed
elongated plates 64 within the release mechanism housing 48. The
elongated smooth plate 80 has a first or forward end 82 and a
second or a rear end 84. The rear end 84 of the arcuately-shaped
smooth plate 80 has a rear pin hole 86 therethrough. The rear pin
34 pivotably securing the toothed plate assembly 62 and the release
mechanism housing 48 also passes through the rear end 84 hole of
the smooth plate 80.
The main toothed plate 62 and the sub-plates 64 with teeth 104,
have an elongated slot 88 extending in a generally forwardly to
rearwardly direction, as may be seen in FIGS. 3, 5 and 7. The slot
88 in the toothed plate assembly 62 has a first or forward end and
a second or rearward end.
The smooth elongated plate 80 has an elongated slot 90 at its
forwardmost end 82, as may be seen in FIG. 8. The slot 90 has a
rearwardmost end portion 93 which is disposed at a slight angle
with respect to the slot 90, as shown in FIG. 8. The smooth plate
80 is arranged to be pivotally juxtaposed adjacent the array of
toothed plate assembly 62 about the rear pivot pin 34, as may be
seen in FIG. 3. The smooth plate 80 has its slot 90 arranged at an
angle with respect to the slot 88 of the toothed plate assembly, as
may be seen in FIG. 3. The slot 90 in the smooth plate 80 has a
first end 92 which is alignable with the front end of the slot 88
in the first or forward end 66 of the toothed plate assembly 62.
The angular relationship of slot 90 with respect to the slot 88
permits the pivotal movement of the smooth plate 80 with respect to
the toothed plate assembly 62. The angled portion 93 of the slot 90
permits the smooth plate 80 to stay in its upwardly pivoted
position. The smooth plate 80 may be pivoted about pin 34,
clockwise (upwardly) as indicated by the arrow "U" shown in FIG. 3,
to move the smooth upper edge 102 of the smooth plate 80 into
position above the teeth 104 on the toothed plate assembly 60, to
thus get the teeth 104 out of engagement with the ratchet point 40
in the frame 16, shown in FIG. 4, when the surgeon wants to keep
the ratchet mechanism in its release mode, as described further,
hereinbelow.
A pair of released buttons 94 and 96 are arranged on each side of
the pair of parallel plates 50 and 52 defining the housing 48 of
the release mechanism 12, as may be seen in FIGS. 1, 2 and 3. The
release buttons 94 and 96 are connected by a button pin 98
extending therebetween, as shown in FIG. 2. The button pin 98 also
extends through the slot 88 in the toothed plate assembly 62 as
well as in the slot 90 of the smooth plate 80, as also shown in
FIG. 2. Moving the release button 94 and 96 to the right as may be
"envisioned" in FIG. 3, would effect the pivoting upwardly
(clockwise) of the smooth plate 80 about its pivot pin 34,
effecting relative movement between the smooth plate 80 and the
toothed plates 62 and 64, thus effecting release of the ratchet
engagement therewith. Movement of the buttons 94 and 96 "forwardly"
would return the ratcheting action into effect.
In operation of the release mechanism 12 of the present invention
the operating surgeon would have fingers arranged through the fixed
handle 20 and in the movable handle 36. Respective arcuate movement
of the pivotable or movable handle, as represented by arrows "A" in
FIG. 1, towards the fixed handle 20 would cause the inner shaft 30
attached to the distalmost end of the movable handle 32 to be
pulled rearwardly and thus effect the closing of the forceps 28 on
the distalmost end 26 of the grasper device 14. When the release
buttons 94 and 96 are in their rearwardmost position, with its
connecting pin 98 within the rearwardmost location of the slot 100
within the release mechanism housing 48 and also in the
rearwardmost position in the slot 88 of the toothed plate assembly
62 and the slot 90 in the smooth plate 80, movement of the movable
handle 32 with respect to the fixed handle 20 is unhindered, thus
permitting the physician to open and close the forceps 28 of the
medical device 14, at will. This is permitted by virtue of the
smooth plate 80 being pivoted upwardly about the rear pin 34, to a
location where the upper edge 102 of the smooth plate 80 is
disposed above the teeth 104 in the toothed plate assembly 62. In
that manner, the ratchet point 40 in the framed portion 16 of the
fixed handle 10 is not permitted to engage the teeth 104 within the
toothed plate assembly 62.
When the movable handle member 32 is pulled rearwardly and the
release button arrangement 94 and 96 is pushed forwardly in its
slot 100 within the release mechanism housing 48,as indicated by
the arrow "F" in FIG. 2, the release button connecting pin 98 is
pushed forward in the slot 88 of the toothed plate assembly 62 as
well as in the slot 90 for the smooth plate 80. The smooth plate 80
is thus cammed downwardly (see arrow "U"in FIG. 3) and pivoted
about its rearwardmost pivot pin 34 and its pin hole 86 due to the
camming action of the release button pin 98 in the slot 90, and out
of its "locked" location in the angled slot portion 93 at the rear
end of slot 80. Thus the teeth 104 in the main toothed plate
assembly 62 (including the attached toothed sub-plates 64) are
exposed to the ratchet point 40 in the fixed handle assembly 10,
and those toothed plates 62 are biased theretoward by the leap
spring 42 within the fixed handle assembly 10, as may be seen in
FIG. 4.
The attending surgeon may thus squeeze the movable handle 32
towards the fixed handle 20 thus ratcheting downwardly on the
handle release assembly 12. This permits the forceps 28 to be
closed in a stepwise manner as per the engagement of the teeth 104
in the toothed plates 62. A body tissue may be thus grasped firmly
within those forceps 28 and held there by the ratchet point 40
engaging any of the series of teeth 104 within the elongated
toothed plates 62 and 64.
Prompt release of the forceps 28 from the tissue is effected by a
downward pressure on the trigger-like bridging portion 54 of the
release mechanism housing 12, as may be seen in FIGS. 1, 2 and 3.
This downward pressure on the bridging portion 54 of the released
mechanism housing 48 pushes the leaf spring 42 downwardly and
permits the movable handle 32 to be displaced away from the fixed
handle 20 thus permitting the opening the forceps 28 and permitting
release of the body tissue from therebetween.
It is thus to be noted, that the unique release mechanism permits a
wide range of angular openings of the forceps, to permit a locking
thereat, thus enabling the operating physician to grasp almost any
size body tissue thereby. The simple release of this mechanism,
being effected by a triggerlike pull on the bridging portion 54 of
the release mechanism housing 48 thus overides the engagement of
the ratchet point 40 with the teeth 104 on the toothed plate
assembly 62, permitting a fast and responsive release of the tissue
and actuating the grasper mechanism 14 for a subsequent grasping
operation.
* * * * *